Ensure acks are sent for all blocking events.

content/renderer/input/input_handler_manager.h

Index: content/renderer/input/input_handler_manager.h
diff --git a/content/renderer/input/input_handler_manager.h b/content/renderer/input/input_handler_manager.h
index bdcaceca1d0880b8475cac977c663e3b288e8104..bb3ef894820fa5bf26e2095eca33509e6b4017fa 100644
--- a/content/renderer/input/input_handler_manager.h
+++ b/content/renderer/input/input_handler_manager.h
@@ -73,7 +73,8 @@ class CONTENT_EXPORT InputHandlerManager {
       const cc::InputHandlerScrollResult& scroll_result);
 
   void NotifyInputEventHandledOnMainThread(int routing_id,
-                                           blink::WebInputEvent::Type);
+                                           blink::WebInputEvent::Type,
+                                           InputEventAckState);
 
   // Callback only from the compositor's thread.
   void RemoveInputHandler(int routing_id);
@@ -118,7 +119,8 @@ class CONTENT_EXPORT InputHandlerManager {
       const cc::InputHandlerScrollResult& scroll_result);
 
   void NotifyInputEventHandledOnCompositorThread(int routing_id,
-                                                 blink::WebInputEvent::Type);
+                                                 blink::WebInputEvent::Type,
+                                                 InputEventAckState);
 
   typedef base::ScopedPtrHashMap<int,  // routing_id
                                  std::unique_ptr<InputHandlerWrapper>>